Field of the Invention:
The invention relates to a temperature-dependent component, in particular a temperature sensor for use in an intake tube for internal combustion engines in conjunction with an air flow rate meter, including a sensor element formed of a temperature-dependent resistor body in the form of a pill, a cube or the like which is secured to a striplike substrate of glass or ceramic and is electrically conductively connected to conductor tracks applied to the substrate, and a resist layer coating the sensor element. The invention also relates to a method for producing the temperature sensor.
Such temperature sensors and components are used, among other fields, in the intake tube of motor vehicle engines, specifically for the sake of precise engine control. The temperature sensor is installed together with an air flow rate meter in the intake tube, between the throttle valve and the air filter.
In one known method for producing temperature sensors with a pair of plug contacts and a resistance element, specifically in the form of disks, pills or the like, the housing, which includes a plug flange and a mounting part that carries the pairs of plug contacts, is produced in one injection molding operation. In a further injection molding operation, an insulating cap is produced, which receives the sensor element in the form of a hot or cold-conductor track (German Published, Non-Prosecuted Patent Application DE 42 37 039 A1).
In another known method for producing components with a temperature-dependent resistance, which are so-called thermistors (JP 4-280602A, Patent Abstracts of Japan, E-1322, Feb. 19, 1993, Vol. 17, No. 85), a plurality of conductor tracks extending in pairs are applied to a substrate, and then sensor elements are each soldered to two conductor tracks located side by side. The sensor elements and the conductor tracks are sealed with a glass layer. Finally, the substrate is severed between each two pairs of successive conductor tracks. The components which are created in that way are relatively wide.
The known temperature sensors are mounted together with their housing in the intake tube, but as a rule their response time is not as fast as precise modern engine control requires.